单项选择题
A.public void DoWork（）；
B.public void DoWork（int nCounter）；
C.public void DoWork（object oCounter）；
D.public void DoWork（Delegate oCounter）；
单项选择题 You are creating a Windows application for graphical image processing by using the .NET Framework 3.5. You create an image processing function and a delegate.You plan to invoke the image processing function by using the delegate.You need to ensure that the calling thread meets the following requirements： （1）It is not blocked when the delegate is running （2）It is notified when the delegate is complete What should you do？（）
单项选择题 YouarecreatingaWindowsFormsapplicationbyusingthe.NETFramework3.5.Youcreateanewforminyourapplication.Youadd100controlsatruntimeintheLoadeventhandleroftheform.Usersreportthattheformtakesalongtimetogetdisplayed.Youneedtoimprovetheperformanceoftheform.Whatshouldyoudo？（）
单项选择题 You are creating a Windows Forms application for a financial service provider by using the .NET Framework 3.5. You have to implement a multiple document interface （MDI） in the application to allow users to open multiple financial documents simultaneously.You need to ensure that whenever the child MDI form is created， the application displays a message in the title bar of the parent MDI that a child form has received focus. What should you do？（）